The present invention relates to a housing for accommodating a planar power transistor having the features characterized in planar power transistor.
It is conventional for power transistors to be arranged hermetically sealed in housings. Planar power transistors have a chip where the functionally doped zones can be contacted by metallized areas. The metallized areas are connected to electric terminals that lead out of the housing for linking the power transistor to a circuit arrangement. Power transistors have three terminals that function as a gate electrode and for connecting to a positive voltage potential and a negative voltage potential.
German Published Patent Application No. 43 27 309 describes that a power. transistor can be arranged in a power transistor package, with the power transistor being arranged in a cast plastic housing, which is electrically insulated. One disadvantage here is that there must be optimum dissipation of the heat generated due to power loss in the power transistor through the plastic housing and/or the relatively small electric terminals. Thus, there are considerable limits to the dissipation of the power loss heat.
The housing according to the present invention, offers the advantage that it permits optimum dissipation of power loss heat generated by a chip in the power transistor. Due to the fact that the housing is formed at least in some areas by at least one of the electric terminals, it is advantageously possible to provide large-area contact over which heat can be dissipated. In addition, the at least one of the electric terminals forming part of the housing may be used to advantage at the same time for assembly of the entire power transistor. Thus, a mechanical and electrically conducting connection of the power transistor to a component carrying a positive and/or negative voltage potential is possible by way of this electric terminal. In particular, it is advatageous if press-fit assembly of the power transistor in a component is possible by way of the electric terminal of the power transistor.